Factors in Chemical Reactions

Concentration and PressureIncrease in concentration means the particles are closer together meaning a greater chance of successful collisionsSurface AreaIncrease in surface area means more particles available to collide and so there's a greater chance of successful collisions

CatalystLowers the activation energy for a reaction and so more particles are available to react - refer to maxwell-boltzmann distribution - and so increases the chance of a successful collision

The Maxwell-Boltzmann Distribution

Not all particles have the same amount of energy. The Maxwell-Boltzmann distribution shows that the majority of particles don't have enough energy to overcome the Activation Energy. This shows the reason for needing to change the factors

Temperature's affect on the MBD

Catalysts affect on the MBD

Catalysts

Catalysts do take part in a reaction but they are chemically unchanged in the overall reaction

Heterogenous Catalyst - catalyst is in a different state or phase to reactantsHomogenous Catalyst - catalyst is in same state or phase to reactants